Many foods eaten by UK children contain a large amount of salt, new research has shown.

And a survey of 2,375 parents for the report found that many didn't realise that popular sweet foods may contain more salt than savoury ones.

For example, only 3% knew that a blueberry muffin contains more salt than two standard bags of crisps (1.1g salt versus 0.5g in each bag of crisps).

And only 10% knew that a serving of Rice Krispie-style breakfast cereal with milk contains more salt than a packet of ready salted crisps (0.65g versus 0.5g).

Sweet foods

Consensus Action on Salt and Health (Cash), which carried out the research with parenting website Netmums.com, wants food firms to lower the amount of salt in children's foods and show salt content clearly on product labels.

The charity is concerned that children who eat more salt are likely to have high blood pressure, and this will carry on into adulthood, raising the risk of having a heart attack.

The Cash research of products on sale this month found an average 100 g portion of Butterkist 'The Simpsons' honey nut popcorn contained 1.25g of salt.

This is 63% of the maximum daily limit for children aged between one and three and 42% of the upper limit for four- to six-year-olds.

Asda pudding

An Asda roly poly fresh 114g pudding had 1.1g of salt - 55% of the recommended daily maximum for youngsters aged under three and 36% for four- to six-year-olds.

Half a pack of Tesco banana-flavour delight made with semi-skimmed milk had 1g of salt.

This is half the upper limit for children aged one to three and 33% for youngsters aged four to six.

Heart attacks

‘Research published just last year showed that children who eat higher salt diets have higher blood pressure than children who eat less salt.

'It is also well established that blood pressure tracks into adulthood. That is, the higher the blood pressure in childhood, the higher the blood pressure in adulthood. Anything that lowers blood pressure in childhood is likely to translate into lower levels of blood pressure in adult life, with reduced risk of developing heart disease and stroke.

‘And it’s not just heart attacks and strokes that are caused by a high-salt diet. Too much salt is also linked with stomach cancer and osteoporosis and can aggravate the symptoms of asthma.’

Added sugar

A spokesman for Monkhill Confectionery which makes Butterkist said its ready-to-eat 'The Simpsons' honey nut popcorn was no longer being made.

A Heinz spokesman said: 'Heinz has been praised for reducing salt in beans, soups, pasta and ketchup and our new Hidden Veg range has lower salt especially for kids.

'But when it comes to our tinned sponge pudding, Cash and the Food Standards Agency accept we would need to add lots more sugar if we took the salt out.'

Which? food campaigner Miranda Watson said: 'It can often be difficult to tell how much salt, fat and sugar are in food products. This is why Which? is calling on food companies across the UK to put traffic-light labels on the front of packs to help parents make healthier choices for their children.'

Which? has commissioned an animated cartoon showing how the marketing of unhealthy food to children increases pressure on parents. It's part of our kids' food campaign, which aims to get companies to stop irresponsible marketing.